The garden in Genesis is a picture of believers (A garden inclosed is my sister, my spouse).
That is why trees are the plants mentioned in it, not asparagus. Trees are pictures of people in the Bible (A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit.) and (that they might be called trees of righteousness,the planting of the LORD).
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Dust is a word for a human (for dust thou art). That is why Satan (the serpent) eats dust (persons)(And the LORD God said unto the serpent, Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life:). Of course, this means that Satan consumes humans spiritually, feeding upon the bad spirit of sinful people.
Someone noticed that God blesses the animals in Genesis. Good noticing. That is because the word blessed is a word always associated with salvation. This is a good way to see that Genesis is written in parable form, since animals must be pictures of people, to have salvation. In like manner, the animals in the ark are pictures of people. Quite frankly, every animal that is mentioned in the Bible is a picture of persons somehow, sometimes including God himself. Here is a good sentence showing a definition of blessed (Blessed is the man unto whom the LORD imputeth not iniquity, and in whose spirit there is no guile.) and (Saying, Blessed are they whose iniquities are forgiven, and whose sins are covered.)